VAG-COM and ELSA do chip tuning on Skoda Octavia I 1.6L

car diagnostic tool

Look here: Skoda Octavia I 1.6L (Simos 3.3) Chip Tuning


Diagnosis of the car Skoda Octavia I

The VAG diagnostic tool is connected …

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  • 17831 – Series 1, accelerated catalyst heating system (P1423 – 35-00 – Low throughput)
  • 16514 – O2 (Lambda) Series 1 probe 1 (P0130 – 35-10 – Fault in the electrical circuit – Not permanent)

Both these and other bugs are known problems of these motors. Therefore, it was decided that the second, with further manifestation, we will solve the traditional method. And from the malfunction of the Secondary Air System (SVB), we will get rid of once and for all, firmware with a decrease in the toxicity standards to EURO2 and the physical removal of unnecessary elements of the system after reflashing.

So, the firmware from ADS ADACT was chosen:

  • Optimized elastic version of EURO2. Allows complete removal of SC (catalyst), DK2 (second oxygen sensor), EGR (exhaust gas recirculation system) and UHV (secondary air system).

Removing the engine control unit in the car Skoda Octavia I

It remains to find where the engine ECU is located and change the program in it. We open ELSA …

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The engine control unit of this car is behind the waterproof casing, in the area of 窶銀€逆he windshield wiper.


We begin disassembly …


… unscrew the wipers, remove the protective cover and before us the motor …


View of the engine installed in the vehicle

As we used to say ” VAG-COM and ELSA pages , the engine control unit, in this car,  Simens Simos 3.3  …

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Connection to the Simos 3.3 block

Inside the block percent: Infineon SAK-C167CR-LM and flash: AM29F400BB .


Judging by the forums, Combiloader works fine with this block in BSL mode. We find Boot pin , this is the 104th processor leg (in the help to Combiloader ‘y have information) …


Now we need to understand the power supply of the unit and the diagnostic line …


Pinout of Siemens Simos 3.3 control unit connectors – Download  (format * .pdf)

Again look in the ELSA …


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Power + 12V – 3rd pin in a large connector, mass – 1st pin in a large connector and to-line diagnostics – 17th pin in the same connector.


The process of chip-tuning the car Skoda Octavia I.

Reading and writing firmware

We try to read the firmware in the BSL mode, the C16x (+ T) module is unsuccessful.


Try to read the firmware in the BSL-mode, the C16x module …


… the operation was completed successfully.


What and where can I see in the firmware of the Simos 3.3 …

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Download the necessary us, the modified firmware and “pour” it into the ECU.


The recording is complete, we collect the block and put it in place.


The results of chip tuning Skoda Octavia 1.6L

  • The electronic engine control unit is loaded with an optimized, flexible version of the firmware, with the EURO2 toxicity standards.
  • The loaded version of the firmware allows for the complete removal of the catalytic converter, the second oxygen sensor, the elements of the EGR system and the BB system. And also excludes the occurrence of errors related to these systems, in particular, errors 17831.